Vintage General Electric 1200W Microwave Oven

Got hold of a old vintage General Electric 1200 microwave overn from the rag and bone man. Did not waste time in opening it up.  Here is the innards, the classic magnetron, the high voltage transformer that weight about 7kg, the high voltage rectifier diode, the electrommechanical time, the cooling fan, the cooking chamber light which is an old fashion 20W incandescent light bulb, the turntable motor, the microswitches that turn off the microwave oven when the door is open, the  over temperature cut off sensor mounted on the magnetron itself. 

Note the mica sheet covering the microwave waveguide opening in the cooking chamber. This is actually a bad design as it exposed the mica sheet to the consumer risking food contamination.

Interesting fact to note is that although General Electric do make magnetrons once, they are now using a LG Electronics ( South Korea )  magnetron, so is the high voltage 1uF capacitor.

In vintage microwave oven like this which uses a high voltage transformer, the cooking microwave power is actually controlled by turning the magnetron on and off at regular intervals. This actually does not gives very precise cooking. Modern microwave oven uses a electronic inverter to supply high voltage to the microwave and the microwave power in this case is controlled by varying the high voltage output pulses.

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The Sony Walkman Is 30 Years Old

I just learned the Sony Walkman just turned 30 years. In 1979 July 1, Sony released a portable cassette player to the market called the Walkman. It can only played recorded cassette tapes.

It was a major leap in portability for consumer electronics. For the first time you can carry a entertainment appliance in your pocket.

As a early tech adopter I bought one of the latter models. this can record to cassette and also has a AM/FM radio. It has a battery that is shaped like a piece of Chiclets chewing gum. I believe this battery is also rechargeable. However the short battery life between recharges causes my interest to wane and this cassette has since been shelved.

Look out for the picture of a vintage Walkman cassette player/recorder, after I dug it out of my junk bin.

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